Solve error time-step too small

x6102104 · June 10, 2019, 20:46

Hello,
How to fix the error time-step<dtmin.
It makes the calculation end.
Thanks

thunde47 · June 24, 2019, 19:39

Please set Minimum time step (dtmin) in the Numerics tab to a smaller value.

MSM1985 · June 25, 2019, 01:43

Do following steps:

1) Check the plot of time step vs stability in the simulation window

2) Keep time step smaller than the time step you saw in simulation graph. This can be done in numerics tab under 'Time Step Controls'

3) As solver is iterating a lot and reducing time step, its better to change the 'Covergence Controls' in 'Pressure Solver Options' in Numerics tab. You can increase maximum number of iterations before time step is reduced. This will also prevent dt<dtmin. error

June 10, 2019, 20:46	Solve error time-step too small	#1
x6102104 New Member Tuan Join Date: Jun 2019 Posts: 5 Rep Power: 7	Hello, How to fix the error time-step<dtmin. It makes the calculation end. Thanks

June 24, 2019, 19:39		#2
thunde47 Senior Member thunde47 Join Date: Dec 2015 Location: India, USA Posts: 133 Blog Entries: 1 Rep Power: 11	Please set Minimum time step (dtmin) in the Numerics tab to a smaller value. cdbot likes this.

June 25, 2019, 01:43		#3
MSM1985 Member Sehroosh Join Date: Apr 2019 Location: Pakistan Posts: 60 Rep Power: 7	Do following steps: 1) Check the plot of time step vs stability in the simulation window 2) Keep time step smaller than the time step you saw in simulation graph. This can be done in numerics tab under 'Time Step Controls' 3) As solver is iterating a lot and reducing time step, its better to change the 'Covergence Controls' in 'Pressure Solver Options' in Numerics tab. You can increase maximum number of iterations before time step is reduced. This will also prevent dt<dtmin. error cdbot and x6102104 like this.

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